vh41de stock tune running lean

[cambo32]

Hey guys, so I hooked up a LC-1 wideband to my vh41de to check the A/F ratios. Once it has warmed up it idles quite lean, +17 so I've been reluctant to run it too long. It starts to blow a whitish sort of smoke but it comes and goes only doing it once warmed up. Im positive its not coolant being burnt, Could the VTC cause this? Its got me baffled cause its a stock ecu and tune and normally they run quite rich from factory.

[cambo32]

So I'm 90% sure that smoke is caused by the inlet valve seals gone bad. Has anyone encountered this before?

[cambo32]

Ended up being valve stem seals. Tried a valve seal treatment oil additive before committing to replace valve seals and it actually worked. Sings on 7k and no smoke. Can hardly believe it fixed the problem. As for ratios it seems to have settled down now. Weird, I wouldn't have thought that oil smoke could give lean readings?